U.S. patent number 4,086,806 [Application Number 05/763,311] was granted by the patent office on 1978-05-02 for seal and actuator for pipe testing.
This patent grant is currently assigned to The Presray Corporation. Invention is credited to George H. Covey, III, Donald D. Stenabaugh.
United States Patent |
4,086,806 |
Covey, III , et al. |
May 2, 1978 |
Seal and actuator for pipe testing
Abstract
In an apparatus for pressure testing open-ended pipes or the
like there is provided a novel sealing means to form an air-tight
seal between the open end of a pipe to be tested and an end plate
of a pipe supporting test fixture. The sealing means comprises a
continuous, annular, yieldable sealing member of triangular
cross-section supported on the end plate. A pneumatically
expandable annular actuator is associated with the continuous
sealing member. The sealing member is normally spaced radially and
axially from the junction area of the pipe end and test fixture end
plate. The pneumatically inflatable actuator is operative to expand
the continuous yieldable sealing element radially and
simultaneously to advance it longitudinally, whereby the triangular
sealing member is tightly wedged into said junction area to form a
preliminary seal. When test pressure is applied, it acts upon the
triangular sealing member to increase the seal effectiveness.
Inventors: |
Covey, III; George H. (Pawling,
NY), Stenabaugh; Donald D. (Pawling, NY) |
Assignee: |
The Presray Corporation
(Pawling, NY)
|
Family
ID: |
25067461 |
Appl.
No.: |
05/763,311 |
Filed: |
January 28, 1977 |
Current U.S.
Class: |
73/49.5; 277/605;
277/616 |
Current CPC
Class: |
F16J
15/46 (20130101); F16L 55/134 (20130101); G01M
3/022 (20130101) |
Current International
Class: |
F16L
55/10 (20060101); F16J 15/46 (20060101); F16L
55/134 (20060101); G01M 3/02 (20060101); G01M
003/28 () |
Field of
Search: |
;73/49.5,49.6,46,49.1
;277/27,34,34.3 ;49/477,479 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
598,160 |
|
Jun 1934 |
|
DD |
|
116,565 |
|
Apr 1969 |
|
NO |
|
Primary Examiner: Queisser; Richard C.
Assistant Examiner: Roskos; Joseph W.
Attorney, Agent or Firm: Mandeville and Schweitzer
Claims
We claim:
1. In an apparatus for pressure testing open-ended pipes of the
like, means to provide a sealing relation between an open end of
said pipe and an end plate of a pipe supporting test fixture, which
comprises
a. a continuous annular, yieldable delta seal member,
b. annular, expandable actuator means associated with and
supporting said delta seal member,
c. mounting means for supporting said actuator means and said
continuous delta sealing member on said end plate,
d. said support means being so configured and arranged as to
position said delta seal member means spaced from the junction
between said open-ended pipe and said end plate, and
e. said actuator means being operative to expand said delta seal
member along a conical envelope toward said junction, whereby the
delta sealing member is wedged into said junction to provide a
sealed relationship between said open-ended pipe and said end
plate.
2. The sealing means of claim 1, further characterized by
a. said actuator comprising a continuous, pneumatically inflatable
actuator including an internal cavity of flat oblong cross-section,
and
b. a source of pressurized air including an air passage means
connecting said source to said cavity whereby the application of
pressurized air to said cavity will expand said actuator thereby
expanding said delta seal member to wedge said sealing member into
said junction.
3. The sealing means of claim 1, further characterized by
a. said continuous, yieldable delta seal member comprising a
continuous elastomeric annulus of generally triangular cross
section.
4. The sealing means of claim 2, further characterized by
a. said mounting means comprising an annular retainer means mounted
on said end plate,
b. said delta seal member and said pneumatically inflatable
actuator being supported on said annular retainer, and
c. said retainer means, actuator and delta seal member being so
arranged and configured as to initially position said delta seal
member spaced from and facing opposite the junction, whereby upon
actuation of said pneumatically inflatable actuator, said delta
seal member will be wedged into the junction.
5. In an apparatus for pressure testing open-ended pipes or the
like, means to provide a sealing relation between an open end of
said pipe and an end plate of a pipe supporting test fixture, which
comprises
a. a continuous, annular pneumatic actuator defining a hollow
cavity of oblong cross-section,
b. means to mount said pneumatic actuator on said end plate,
c. an annular sealing member associated with said pneumatic
actuator and adapted to be tightly received into the junction area
between the open end of said pipe and said end plate to form an
air-tight seal,
d. said sealing member being normally spaced from said junction
area,
e. a source of pressurized air connected to said cavity whereby the
application of pressurized air to said cavity will cause the cavity
to expand thereby causing said pneumatic actuator to expand said
sealing member to be tightly received into said junction area.
6. The sealing means of claim 5, further characterized by
a. said sealing member comprising a continuous, elastomeric annulus
of generally triangular cross-section,
b. a continuous slot being formed in one surface of said sealing
member,
c. said pneumatically inflatable actuator including a continuous
integral projection adapted to be received and secured within said
slot,
d. the remaining two surfaces of said sealing member forming
sealing surfaces and being adapted to be wedged into the
junction,
e. whereby when said cavity is expanded, said sealing member will
be expanded and wedged into said junction.
7. The sealing means of claim 6, further characterized by
a. said sealing surfaces intersecting at an angle slightly greater
than 90.degree..
Description
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention is related to the pressure testing of
open-ended large diameter pipes. After the manufacture of a section
of large diameter welded pipe, for example, the pipe is typically
subjected to pressure testing in order to determine whether the
section has been properly formed and is air tight. The pipe section
is mounted between end plates of two opposed test fixtures, which
support the pipe and form an air tight seal at the open ends
thereof. Pressurized air is then pumped into the interior of the
tubing or pipe. Tests may then be conducted to determine whether
any air is leaking from the pipe interior to the surrounding
atmosphere.
In testing apparatus of the general type described above, it is
important that the pipe be easily mounted on the test fixture and
that a leak-tight seal at the junction of the pipe under testing
and the test fixtures be readily formed. Further, it is of
significance that the testing procedure require no mechanical
attachments and that it be non-damaging to the pipe, so that
fiberglass, non-ferrous and similar pipes can be accommodated, as
well as steel pipes.
It is an object of the present invention to provide an improved and
more effective sealing means to be mounted at the end plates of
test fixtures of the type being referred to. The sealing means is
adapted to be operable upon the placement of an open end of the
pipe to be tested in abutting relation to the end plate, to form an
efficient air-tight seal. In its broadest scope, the present
invention provides a continuous yieldable, radially expandable
sealing member at each end plate. Each sealing member is adapted to
be expanded so as to be tightly received into the junction area
between the open end of the pipe and the complimentary test fixture
end plate. Novel, pneumatically expandable actuator means is
associated with each sealing member and is also supported on the
circular end plates of the test fixtures. The sealing member and
actuator means are so arranged on the end plate that the sealing
member is normally spaced from the junction area along an angular
axis. When it is desired to form the air tight seal, the
pneumatically inflatable actuator is actuated to expand the
continuous sealing element along a conical envelope and thereby
wedge the sealing member tightly into the junction area to provide
the seal.
Advantageously, the continuous sealing member comprises a
continuous rubber annulus of generally triangular cross section,
sometimes referred to as a "delta seal" member. The delta seal
member is initially expanded and advanced longitudinally to contact
both the pipe inner wall and the end plate in the junction area.
The delta seal member easily conforms to the configuration of the
junction area whereby the seal may be easily wedged therein under
test pressures acting on the "base" of the triangular cross
section.
According to one aspect of the invention, the actuator means
comprises a continuous annular pneumatic actuator including means
to connect the actuator to the end plate and additional means to
connect the actuator to the continuous delta seal member. The
annular actuator, which is formed of elastomeric material, defines
a hollow cavity. In its normal, unactuated condition, the
elastomeric member is of a flat, oblong cross-section and supports
the delta seal member in a retracted position, spaced axially from
the end plate and radially contracted to a diameter less than the
inside of the pipe. When the open end of a pipe to be tested is
placed in abutting relation to the end plate, the actuator is
inflated by fluid under pressure applied to the hollow cavity of
the actuator. This will tend to expand the annular actuator member
along a conical envelope whereby the delta seal member is expanded
radially and also advanced longitudinally toward the end plate. The
delta seal member is thus wedged into sealing position at the pipe
end-test fixture junction.
When the test pressure is applied to the interior of the pipe, it
will place an outwardly directed pressure on all the exposed
surfaces of the test pipe, test fixture end plate and delta seal
member. The outwardly facing sealing surfaces of the delta seal
member intersect to form an angle of slightly greater than
90.degree.. This will cause the end portions of these surfaces to
contact the pipe interior and test fixture end plate respectively
before the apex of the angle of intersection of the surfaces. The
test pressure directed against the delta seal member will tend to
wedge it further into the junction of pipe end and the test
fixture, thereby increasing the sealing effect of the delta seal
member independently of the inflatable actuator.
For a better understanding and appreciation of the above and other
features and advantages of the invention, reference should be made
to the following detailed description of a preferred embodiment of
the invention and to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS:
FIG. 1 is a side view of a test apparatus for pipes including a
partial cross-sectional view of one end thereof to illustrate
features of the present invention which are incorporated
therein.
FIG. 2 is a cross-sectional end view of the test apparatus and
taken generally along line 2--2 of FIG. 1.
FIG. 3 is a cross-sectional view taken generally along line 3--3 of
FIG. 2, of the delta seal and actuator of the invention in the
retracted position and
FIG. 4 is a view of the delta seal and actuator of FIG. 3 in the
actuated position.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Referring now to the drawings, and initially to FIG. 1, there is
illustrated a testing apparatus for the pressure testing of
open-ended pipe. A test pipe 10 is removably supported between two
test fixtures 11, 12. The test fixture 12, at the right hand side
of the test apparatus, may be fixedly mounted and includes an air
passage 13 which opens on circular end plate 14. The air passage 13
is connected to a suitable source of pressurized air (not shown)
for supplying test air to the interior of the pipe 10.
To facilitate the mounting of the test pipe 10, the test fixture
11, at the left, is provided with wheels 15 which ride on tracks
16. An actuating rod 17 of any conventional actuator, for example a
fluid actuator operable through a predetermined stroke (not shown),
is connected to the test fixture 11 by a connecting pin 18. The
actuator rod 17 is initially retracted to a far-left position, and
the test pipe 10 is placed between the two test fixtures 11, 12.
The right hand end of the test pipe 10 is placed in a
perpendicular, abutting relation to the end plate 14 of the test
fixture 12. At this time, the actuator rod 17 may be moved to the
right thereby moving the test fixture 11 on the tracks 16 until the
circular end plate 19 is in abutting relation to the left hand end
of the test pipe 10.
In accordance with the present invention, each of the end plates
14, 19 is provided with a continuous, yieldable sealing element 20
adapted to form an air tight seal between the ends of the test pipe
10 and the end plates 14, 19 respectively. The right hand end of
the test apparatus of FIG. 1 is shown in cross section to
illustrate the sealing means of the present invention, and the
detailed description will refer to this portion of FIG. 1. However,
it is to be understood that an identical sealing means arrangement
is provided at the end plate 19.
In its preferred form the sealing element 20, sometimes herein
referred to as a delta seal member, comprises a continuous rubber
annulus of generally triangular cross-section, as best illustrated
in FIG. 3. The delta seal member 20 includes two sealing surfaces
20a, 20b which are disposed at an angle slightly greater than
90.degree. and are adapted to be wedged into the right-angular
junction area between the end of the test pipe 10 and end plate
14.
A continuous, pneumatically inflatable actuator 21, formed of
elastomeric material, is provided with an integral continuous key
projection 22 which projects from one side of the actuator and is
adapted to be received into a complimentary dove-tailed slot 23
formed in the back face of the delta seal member 20. The other side
of the actuator is provided with an integral continuous T-shaped
flange 24. An annular retainer 25 is formed to include an annular
slot 26 with overlying flanges 27 whereby the T-shaped flange 24 of
the pneumatic actuator 21 may be secured in the annular slot
26.
Pursuant to one aspect of the invention, the annular retainer 25
supports the actuator 21 and seal 20 at an angle (advantageously
about 45.degree.) to the axis of the pipe. Accordingly, when the
actuator 21 is inflated, both it and the delta seal member 20 will
expand along a conical envelope which substantially intersects with
the annular junction between the pipe end and the plate 14. This
will properly position the delta seal 20 with respect to the
junction of the end of the test pipe 10 and end plate 14, as will
be understood.
A plurality of perpendicular support posts 28 are secured to the
end plate 14, as by welding, reflected at 29, with each being
spaced a predetermined distance from the circumference of the end
plate 14 to form an annular array. The annular retainer 25 has an
internal diameter which is slightly greater than the diameter of
the annular array of the support posts 28, whereby the retainer 28
may be received over the support posts 28 and secured thereto by
welding, as reflected at 30. The annular retainer 28 is positioned
so that the flanges 27 are spaced from but generally toward the end
plate 14. This will place the retracted delta seal member 20 at a
position spaced axially from the end plate 14 and radially from the
pipe wall, but in alignment with the junction between the end plate
14 and test pipe 10, as clearly illustrated in FIGS. 1 and 3.
Referring now to FIG. 3, the rubber pneumatic actuator 21 defines a
continuous hollow cavity 31. The cavity 31 has a flat, oblong
cross-section when the actuator 21 is in its normal, deflated
state. After the test pipe 10 has been placed between the test
fixtures 11, 12 as described above, pressurized air may be applied
to the cavity 31 via a passage means which may run along the path
defined by the dashed line 32. Typically, the air is under a
pressure of about 40 psi. The pressurized air will cause the
actuator to expand, as shown in FIG. 4, thereby expanding the delta
seal member 20 along a conical envelope toward the pipe end plate
junction. This will cause the sealing surfaces 20a, 20b of the
delta seal 20 to be wedged into the junction area between the test
pipe 10 and end plate 14 to form an air tight sealing
relationship.
To particular advantage, the sealing faces 20a, 20b intersect at an
angle slightly greater than 90.degree.. Thus, the end portions 33
of the sealing faces 20a, 20b will contact the test pipe 10, and
end plate 14 before the apex of the angle of inter section of the
sealing surfaces 20a, 20b. As reflected in FIG. 4, this will cause
the back face of the delta seal 20 to be slightly deformed into a
curved surface whereby the sealing surfaces 20a, 20b will be
pressed against the pipe 10 and end face 14 to insure a tight
seal.
After the test pipe 10 is initially sealed to the end plates 14, 19
by inflation of the actuator, pressurized air may be fed to the
interior of the pipe through air passage 13 for testing purposes.
Typically, the test air pressure is at least 100 psi. This
pressure, being greater than the inflation pressure of the
actuator, will tend to collapse the expanded cavity 31, however,
the test air pressure will also be directed against the back face
of the delta seal member 20, urging it against the pipe and plate
surfaces to increase the sealing action thereof.
The present invention provides a straight forward, extremely
effective sealing means for large diameter pipe testing apparatus.
When the actuator 21 is in its normal unactuated state, the delta
seal element 20 will be spaced from the junction area of the test
pipe 10 and end plate 14. Thus, the test pipe 10 may be easily and
quickly positioned against the end plate for mounting. To form the
air-tight seal, pressurized air is simply applied to the cavity 31
of the rubber actuator 21 to expand the actuator 21 along a conical
envelope and thereby wedge the delta seal member 20 in the sealing
position.
The novel arrangement of annular retainer 25, actuator 21 and delta
seal member 20 advantageously positions the delta seal in an
initial retracted position, spaced from the junction area. This
facilitates an unobstructed test pipe 10 mounting procedure,
thereby simplifying and expediting the overall test procedure.
It should be understood, of course, that the specific form of the
invention herein illustrated and described is intended to be
representative only, as certain changes may be made therein without
departing from the clear teachings of the disclosure. Accordingly,
reference should be made to the following appended claims in
determining the full scope of the invention.
* * * * *